A reel line guide device for use in a baitcast reel is disclosed, the reel line guide device including: a mount provided with a mounting position for accommodating a reel assembly; a guide arranged on the mount and positioned on one side of the mounting position, the guide being provided with a passage hole for a fishing line on the reel assembly to pass through; and a button transmission mechanism arranged on the mount and including a button assembly and a transmission assembly, the transmission assembly being connected to the button assembly and the guide to drive the guide to rotate under the action of the button assembly, so as to adjust an angle of the passage hole of the guide relative to the reel assembly. A baitcast reel having the above-mentioned reel line guide device, and a fishing tackle are further disclosed.